Incinerator



Oct. 18, 1960 H. HARTMANN INCINERATOR Original Filed Aug. 22

INVENTOR. HENRY HARTMANN 4 f j M i.

United States Patent 'INCINERATOR Henry Hartmann, 67 Bayside Ave.,Amtyville,'-N.'Y.

substituted for abandoned application Ser. No. 529,803, Aug. 22, 1955.This application Dec. 8, 1958, Ser. No. 779,029

v1 Claim. (Cl. 110-18) This invention relates to an .improved method andapparatus for burning refuse and, in particular, to burningorincinerating methods and devices to beused in areas where, due todensity of population or proximity to densely populated areas, it isdesirable toeifect complete combustion of the waste without substantialVresidual smoke or odor.

lHeretofore, it has been the practice to burn refuse inmultiple-dwelling units such as Yapartmenthouses in incineratorscomprising essentially a combustion Vchamber-located in the vicinity ofthe basement of uthe building. AIn `order vto support the incineratorload the combustion chamber vis provided with a grate. vExtending fromthe top of the combustion chamber there vis a liiue to the roof ofthebuilding to carry away combustion products. vA multiplicity of refusefeed chutes are supplied on the various floors of the building .so .that'the 4be provided with an auxiliary burner which is .fin constantoperation to initiate and maintain combustion of the refuse.

There are many disadvantages attendant to the type of operation andapparatus heretofore employed. A serious problem is the tendency to formaerosols of unburned or incompletely burned refuse. Such Yaerosols areextremely objectionable to the environs'because they are malodorous andalso tend to soil household fabrics and furniture.

Efforts have been made to dispose of such aerosols by treating the flueproducts by incinerating themin a second stage incinerator at a pointremote from the combustion chamber or by injecting a secondary llameinto the combustion chamber at a point above the primary combustionzone. Secondary combustion in fa zone remote from the primary combustionzone, in elec't, requires the provision of two incinerators to take careof a single load of refuse, which increases the investment with noincrease in capacity of the unit. Furthermore, the secondary combustionzone also requires its supply of auX- ililary heat so that operatingexpenses, in eifect, are also increased substantially. Moreover, knownfume incinerators have not been designed for effective and economicaloperation.

Direct injection of a secondary combustion ame into the primarycombustion chamber has not provided a satisfactory solution to theproblem for several reasons, among them being the difficulty inproducing complete combustion of the aerosols and diiculty in making allthe aerosols pass through the secondary incinerating ,ame which isnecessary to assure complete combustio-n of the aerosol. Furthermore, byuse of the secondary flame there is no assurance that the temperature ofthe aerosol will be raised to the necessary level and will bem-aintained at the temperature level for time necessary to producecomplete combustion. The tendency has been to use an excessive amount ofsecondary fuel vin an effort to assure complete combustion of aerosols,

.and this,. in turn, has produced excessive temperatures in theiiue ways`and excessive drafts with consequent invcreasein :amountof ily ashcarried upward Ithrough the ue.

The advantages of the present invention include the provision of amethod and apparatus which aifordcomplete incineration of aerosolseciently and economically. vAnother,advantage is theavoidance ofexcessive temper- .atures ofthe iluegases. .Still another advantageresides in Vthe control of the draft yin the incinerator to avoid flyashsuspension. Furthermore, the apparatus provided according -to ltheinvention is simple as compared with incinerators heretofore designedwhich have required theuseof cumbersome baiesthought to be .necessaryto. create turbulence.

The foregoing advantages .are realized .according to the .invention byproviding that .the products of the basic. combus-tion process ofvincineration including excess `air andincompletely burned material,some of which .may bein aerosol form, are induced to p-ass through aduct or ue Idescribed more fully hereinafter within the main combustionchamber. Inthis duct incineration 'of the `unburned vand/or incompletelyburned material .ucts and dehydr-atingand more complete burning of theload. The design of theduct and .associated .port-ions of theincinerato-r are preferably such that, having in .mind the :amountandnature of material to be burned, optimum heat transfer conditions aremaintained between Vthe duct and the load in the -main `combustionchamber.

The nature o-f the invention maybe more clearly understood by referenceto the Iattached-drawings considered together with .the'followingdescription:

Figure 1 is an elevation view in the-section, the section being taken onra plane indicated `by line 1--1 of Figure 2 looking .in the directionof the arrows;

Figure y2 .is a horizontal -section .taken on a plane .indicated by theline 2-2 of .Figure 1 looking .in the direction of thearrows; .and yY:Figure n3' is a vertical section view taken on a plane indicated by aline 3-3 of .Figure `1 'looking in the direction of the arrows.

Figure 4 is a perspective View of Aanother type of incinerator with aportion of the exterior walls broken away to show the interior of .theapparatus.

Referring to the drawings, at 10 there -is shown a main combustionchamber having a grate 11 which supports the incinerator load 12. Themain furnace wall 15 which may be ordinary brick is completely linedwith tire brick 16 within which the combustion chamber 10 is formed. Theportion of the tire brick liner 16 which forms the roof 17 of thecombustion chamber is supported by str-aps -20 from a beam 21. Anupwardly extending flue is sho-Wn at 25 with charging chutes 26 forintroduction of refuse thereto and eventually to t-he combustion chamber1t) in the manner presently to be described. Doors 30 and 31,respectively are provided for the purpose of observing the burning loadand cleaning out ash from below the grate 11 and providing overre andunderire air. So much of the apparatus has been 'heretofore known.

Supported within the main combustion chamber 10 by the braces 35 is athin-walled duct or flue 36 which has two turns, one at 37 and the otherat 40, with passageways on both sides of each turn thereby providing atortuous path for gasses passing through it. The inlet f to theinvention is carried out as follows. combustible material is introducedto the chamber supported on the grate 11 either through the doors 26opening to the ue 25 (while doors 466, 67 are open), or

secondary combustion zone.

end 41 which is spaced from the refractory wall 16 is tted with a collar42 which provides a connection with the wall. The collar 42 has openings34 which permit entry of the products of combustion of the mainincinerator load 12 to the duct 36, While stopping large pieces ofpaper, etc. which may tend to be entrained with the gases. The collar 42may have associated therewith an auxiliary burner 46 on the outside ofthe furnace which is connected to collar 42 by a pipe 47 passin throughthe walls 16 and 15.

The duct or ue 36 may be formed of any material that will withstand thetemperatures prevailing and which has suiciently high heat conductivityto yfulfill the objects and provide the advantages of the invention.Thinwalled refractory material or high temperature metallic alloys maybe mentioned as suitable materials of construction.

A Yframe 55 is mounted in an upper corner of the combustion chamber 10secured to the refractory walls 16 and ceiling 17 in the manner shown.The frame 55 is most suitably formed of a metal which will resist thehigh temperature of the gases with which it comes into contact. Formedlat one end of the frame 55 is an elongated mixing chamber 51 which hasan elongated opening 56 that is in substantially gas-tight contact withthe elongated and narrowed discharge end 50 of the duct 36. The mixingchamber 51 has an elongated rectangular discharge opening 57 which is indirect communication with the open central portion 60 of frame 55 Iandthe open top 61.

One end of the mixing chamber 51 is connected in gastight fashion with acooling air duct 62, shown most clearly in Figures 2 and 3.

through it may be controlled for purposes hereinafter described.

At the lower portion of the frame 55 there are pro-v 67 may be opened orclosed by means of rods 75 and 76 The duct 62 passes through the walls15 yand `16 and is provided at its inlet end with "a damper 65 in orderthat the amount of air passing operated from outside the furnace byhandles 77 and 80.

j Securing means 81 and 82 such as ratchet and pawl devices are providedoutside the furnace which in cooperation with the rods 75 and 76 may beused to secure the -position of the doors 66 and 67, respectively, inthef closed position.

The doors may be held open by gravity. The operation of the apparatusdescribed according A load of through the door 30 in the main furnaceWall. Before the combustion in the chamber 10 has been established, thedoors 66 and 67 are closed by manipulating the hanf dles 77 and 80,respectively, thereby to prevent by-passing of combustion products fromthe combustion chamber 10 i I aerosol form, then will be obliged to passthrough the openings y45 in the collar 42 and the inlet end 41 of lduct36. The gasses are mixed by turbulence `as they enter'the duct toproduce a more uniform tempera-ture, and are then heated by heat fromthe burning load It will be observed that the duct is in directunobstructed radiation and convection heat interchange relationthroughout its length with the burning load so as to facilitate combustion in the primary combustion chamber and also in the Some o-f the heatgenerated 'transmitted through the wall of the duct.A Secondarycombustion of the unburned material takes place, and v'duct 36,therefore, becomes very hot.

4 within the duct 36 passes through the walls of the duct and istransmitted by radiation back -to the load 12 so as to assist materiallyin maintaining combustion of the load. Some of the heat from the ductalso passes through the wall and is transmitted by convection to thegases 4in the primary combustion chamber. Alternatively, such gases maysupply heat to 4the duct by convection and radiation, according to localconditions.

The design of 4duct 36 is dependent on the quantity of unburned materialsuch las aerosols in the combustion products entering the duct. Thevelocities, the length of the passage through the duct, and the numberof turns traversed yield the proper time, temperature and turbulencerequired to incinerate the aerosols within the confines of thecombustion chamber, i.e., inside of the duct 36. To promote heattransfer from the burning load to the gases inside the duct 36 and alsoin a reverse direction, i.e., from the hot products of secondarycombustion inside the duct 36 through the walls of the duct and back tothe load, the duct 36 is most suitably constructed of material which hasa highest feasible heat transmission rate, i.e., thin-walled refractoryor high ternperature metallic alloy. Furthermore, inasmuch as heattransmission rate is improved by turbulence of the gases owing -throughthe duct 36, the duct is most preferably formed with at least one turnsuch as those shown at 37 and 40 of Figure 2. If desired, the secondarycombustiontaking plac inside the duct 36 may be initiated and/ormaintained by an externally disposed auxiliary burner 46 which isadapted to inject a flame of burning oil or gas through the pipe 47 anddirectly into the inlet end 41 of the duct 36. The stream so intoducedmay produce some asperating eiect and thereby draw combustion productsthrough yand/ or from below or above the grate 11.

The products of secondary combustion pass through the discharge end 5t!of the duct 36 into the mixing l chamber 51. At this point cool outsideair, the flow of which is controlled by the damper 65 and which entersthrough the duct 62, is ymixed with the hot combustion products so thatthey become cooled to'a substantially lower temperature as desired. Theintroduction of air through the duct 62 also provides a control of thedraft in the combustion chamber 10, thereby minimizing the suspension offly ash in the combustion products. Cooled gases leave the mixingchamber 51 through outlet port or opening 57, thence into the centralportion 60 of the frame 55 and through the open top 61 of the frame intothe flue or chimney 2S. The outlet gases thereby are delivered to theflue or chimney substantial-ly free of undesired aerosols and odors andin a substantially cooled condition so as to involve minimuminconvenience and hazard from overheated chimney flues.

As previously indicated, the doors 66 and 67 are closed to prevent thedirect by-passing of combustion products from the combustion chamber 10into chimney 25. If any refuse is charged to the chimney 25 `during theincineration process it will rest on the doors out of the path of thegaseous ue products from the mixing chamber 51, ready to be charged tothe combustion chamber 10 for a subsequent incineration cycle.

Referring to Figure 4, the incinerator shown was exterior refractorywall '90 formed by four vertical Wall portions 91, 92, 93 and 94. Thefour walls and ceiling 95, and a grate not shown in the drawing, form aprimary combustion chamber to burn ya load of refuse 97. A chimney 99 isbuilt above the furnace as shown, and suitable partitions that are inpart shown as broken away and in part arenot shown, are provided toprevent direct ow of the gas from the primary combustion chamber to `thechimney.

A thin-wall duct 100 is mounted in the primaly combustion chamber and isformed of three Ysubstantially ystraight passageways 101, 102 and 103.The `respective -passageways are connected by the turns 105 and 106. Theduct 100 is mounted within the primarycombustion chamber by suitablesupports, not shown,-theinlet end 107 of the duct 100 being jprovidedwith an expanded metal screen 108 having apertures 109 to permit Avtheentrance of gases from the primary combustion chamber to the duct. ItAwill be noted tha-tthe Yinlet end 107 is mounted so that Tit `is spacedfrom .the Walls 91 92.

At the outlet end of Vthe duct '100, there is a grating 110 to permitaccess of theduct e'iuent :to the chimney 99 and to prevent the entry of`refuse into the duct. By means of the partitions referred to, the gasesleaving the primary combustion chamber, therefore, are constrained toflow -into the duct 100 through the openings v109 and thence directlyinto the chimney through the grating 110.

The auxiliary burner 112 is mounted outside the -furnace wall 92 and isconnected by suitable piping extending through the wall to the inlet end107 of the duct 100. The burner 112 is connected to a supply of gas orother fuel and adapted to inject a llame substantially axially into theinlet end of the duct 100 to initiate or support secondary combustion.

A horizontal sliding door 114 is mounted in a pair of channels 115 andis supported on a pair of rollers 116 that travel on the upper portionsof the channels 115. The gaskets 115' which are around the edges of thedoor 114 provide a seal. A long rod 117 is connected to the door and hasa handle 118 for 4manipulation and adjustment by the operator. It willbe observed that the door 1114 also is necessary to complete the sealbetween the primary combustion chamber and the chimney so as to requirethe gases to ow through the duct 100 and prevent the escape of aerosolsto the chimney.

In the upper portions of the chimney 99 there are provided one or ymoreaccess chutes (not shown in the drawing) in the same manner as`described and shown in connection with Figure l. The refuse, therefore,may be charged to the incinerator through the chimney directly to theprimary combustion chamber during the non-burnoff period, while thesliding door l114 is retracted. When -it is desired to start theincinerator, the operator slides the door 114 closed. Thereafter, theoperation may begin.

A duct 120 is provided in the brickwork construction to providecommunication of the chimney 99 with the outside. An adjustable door ordamper 121 is mounted at the inlet end of the duct 120 to control theflow of air. By adjusting the door 121, the amount of cool airintroduced into the chimney can be controlled, the cooled air mixingwith the hot combustion products leaving the grate 110 in a mixing zoneat the position shown approximately at 123 in the lower portion of thechimney 99. In this way the temperature of the chimney gases is reduced,the draft is controlled, and the amount of iiy ash is maintained at aminimum, as described in connection with the other embodiment of theinvention.

Below the duct 120 there is another duct 125 having an entrance 126below the level of the grate, a damper with control handle 127, la bend130, and a horizontal portion `131 terminating in a discharge port 132located at a point in the furnace remote from lthe inlet end 107 of theduct 100. The purpose of the duct 125 is to regulate the amount of kandthe point at which overiire air is introduced.

A door 135 is mounted in the front wall 92 of the furnace which also maybe used for the introduction of over-fire a-ir. Another door 135 is alsomounted in the wall 92 below the door 135. The purpose of the vTheamount of airis lsufficient to provideoxygen for lpri- 10 `maryv-corribustion in the primary combustion chamber,

and for secondary combustion in the duct 100. Some Ysecondary air may beadded ator near the loca-tion of vthefburner 112. Thus, an annular space(not shown) faroundthe burner where it passes through the wall may :beprovided to allow the entry-of secondary air. The

primary combustion products and secondary air enter :the duct11`00through the openings 109, after which they are 'mixed vWithin `the ductto a substantially uniform .temperature The achieving ofthe necessarytempera- .ture and turbulence to V,maintain vcorrngrlete combustion .of.the aerosols within theduct is facilitated by the Itortuous path of thegases through the duct provided by the turns 105, 1106. Accordingly, theheat generated in the duct by secondary co-mbustion of the aerosolsflows through the thin duct walls to heat the surrounding aerosolcontaining gases and the load 97 by convection and radiation.

The eflluent of the duct 100 ows into the mixing zone 123 where it ismixed with cooled air entering through the duct 120. The relativepositions of the lower duct 125 (for introducing overire air) and duct120 (for introducing cooled air to the chimney) contribute to thedesired functions of the two ducts. Thus, the horizontal portion 131 ofduct 125 absorbs heat from the burning load 97, thereby preheating theoverre air and facilitating maintenance of high and uniform temperaturesin the primary combustio-n chamber. This tends to keep the air -in theduct cooler so that it performs its function of cooling the efliuentgases very effectively and protects the material of the duct and doorfrom overheating.

It will be apparent that the conditions maintained within the secondarycombustion zone are those under which substantially all of even the mostrefractory aerosols are burned, and that such conditions are produced bymixing the gases so that there is uniformity by maintaining the gases atthe required temperature for the necessary time. The time is held asshort as possible by increasing turbulence and temperature.

The gases containing aerosols owing outside the duct, which may be at atemperature somewhat below the ternperature of incineration and ignitionof lthe aerosols, flow into the end of the duct and thence to thesecondary combustion zone, where the ignition is initiated by anauxiliary flame and the aerosols are burned. The heat of combustionflows through the thin-walled duct to preheat the external gases byradiation and convection, thereby tending to maintain the desiredconditions Within the duct by heating the gas toward the ignitiontemperature. lf the incoming gases are substantially below the ignitiontemperature of the more refractory aerosols (1500 F.), the auxiliaryIburner will be needed to initiate and maintain combustion in the duct.However, if the temperature of the gases, air and aerosol mixtureentering the duct is high enough, the part of the heat that is returnedto the incoming gases will be sufcient to continue complete incinerationwithout any auxiliary fuel.

Although specific embodiments of the invention have been described inthe preceding presentation, it will be apparent to those skilled in theart that the invention has many modifications and equivalents Within itsspirit and scope. For example, the duct or ue 36 may be heatedelectrically rather than b-y an external auxiliary burner as shown. Theprocess and apparatus described may be applied to other incinerationprocesses in industrial and 7 commercial applications. Accordingly, -itis intended'that al1 such modifications and equivalents shall beincluded within the scope of the appended claim of the invention vasdeiinedin the appended claim.

n I claim:

An incinerating system having a pnimary combustion chamber for burning aload of refuse and a chimney ,for exhaust gases through which refuse maybe charged to said primary combustion chamber, comprising a ductcompletely conrined within said chamber and in heat interchange relationwith said burning load, said duct having an inlet adapted to receive theproducts of combustion of said load and an outlet for discharging gases,an auxiliary burner mounted outside of said primary combustion .chamberand adapted to inject a ame axially into the inlet end of said duct andthereby initiate and maintain `secondary combustion therein, said ducthaving at least one turn to provide a tortuous path for gases flowingthrough it, a mixing chamber between the discharge end of said duct andsaid chimney and adapted to receive gases discharged from said duct, anair duct adaptedrto convey `8 cool to said mixing chamber so as to lowerthe tentperature of said gases in said mixing chamber before they aredischarged to said chimney and control the draft in said primarycombustion chamber to reduce-the amount of suspended y ash risingtherefrom, and an youtlet from said mixing chamber to discharge saidcooled gases to said chimney, a door controlled from outside the systemso mounted that it prevents the .by-passing o f primary combustionproducts from. said primary combustion chamber to said chimney when itis closed, and permits charging of refuse deposited in said chimney tosaid primary combustion chamber when it is opened.

References Cited in the 'rile of this patent UNITED STATES `PATENTOFFICE CERTIFICATE 0F CORRECTION Patent No. 2,956,526 October 1960Henryv'ldartmann It -s her-eb'- -cerbif ed that'errorrappearsn'bhewpr'nted specification of the above lnumbered patent requiring.corrrecfbiomandw'bhafb,.themsad.Letters Patent should read as correctedbelow.

Column 3V line 3l for "34" read 45 Signed and sealed this l11th day ofApril 1961.

C SEA L) Attest:

RNEST WQ lSW1-DER Attesting Officer ARTHUR W. CROCKER ActingCommissioner of Patents

